Merge pull request #6 from smdthiranjaya/dev

Clean and add comments for the whole project.

server.js

@@ -8,24 +8,33 @@ const swaggerUi = require('swagger-ui-express');
 const swaggerDocs = require('./src/swaggerConfig');
 const subscriptionRoutes = require('./src/routes/subscriptionRoutes');
 
-const app = express();
+// Initialize Express app
+const app = express(); 
+ // Enable CORS
 app.use(cors());
 
+// Parse JSON request bodies
 app.use(express.json()); 
+// Use weather routes
 app.use(weatherRoutes);
 
-app.get('/', (req, res) => {
+// Root endpoint
+app.get('/', (req, res) => { 
   res.send('Weather Data Fetching Service is running.');
 });
 
-app.use('/api-docs', swaggerUi.serve, swaggerUi.setup(swaggerDocs));
-app.use('/api', subscriptionRoutes);
+// Use swagger doc routes
+app.use('/api-docs', swaggerUi.serve, swaggerUi.setup(swaggerDocs)); 
+// Use subscription routes
+app.use('/api', subscriptionRoutes); 
 
-setInterval(() => {
+// Schedule email updates (6 hours)
+setInterval(() => { 
   sendWeatherUpdates().catch(console.error);
-}, 43200000); 
+}, 21600000);
 
-setInterval(async () => {
+// Schedule weather data updates (5 minutes)
+setInterval(async () => { 
   try {
     await updateWeatherDataManually();
   } catch (error) {

src/config/index.js

@@ -1,5 +1,6 @@
 require('dotenv').config();
 
+// Export configuration settings
 module.exports = {
   PORT: process.env.PORT || 3000,
   DATABASE_URL: process.env.DATABASE_URL

src/controllers/subscriptionController.js

@@ -1,15 +1,18 @@
 const pool = require('../db'); 
 
+// Define an asynchronous function to add a subscription
 async function addSubscription(req, res) {
     const { email, city } = req.body;
     try {
+        // Connect to the database
         const client = await pool.connect();
         const insertQuery = `
             INSERT INTO subscriptions (email, city)
             VALUES ($1, $2)
             RETURNING *;
         `;
         const result = await client.query(insertQuery, [email, city]);
+         // Release database client back to pool
         client.release();
 
         res.status(200).json({
@@ -26,5 +29,6 @@ async function addSubscription(req, res) {
     }
 }
 
+// Export the addSubscription function
 module.exports = { addSubscription };
 

src/controllers/weatherController.js

@@ -1,9 +1,11 @@
 const { storeWeatherData, fetchAllWeatherData } = require('../models/weatherModel');
 const pool = require('../db'); 
 
+ // Function to manually update weather data
 async function updateWeatherDataManually() {
     console.log('Fetching and Storing weather data...');
 
+    // Define static data for cities and geo locations
     const cities = [
       { id: 1, city: 'Colombo', lat: 6.932, lng: 79.848 },
       { id: 2, city: 'Kandy', lat: 7.296, lng: 80.636 },
@@ -23,6 +25,7 @@ async function updateWeatherDataManually() {
   ];
 
 
+  // Generate and map mock weather data for cities
     const weatherIconMapping = {
       'Sunny': 'https://cdn.worldweatheronline.com/images/wsymbols01_png_64/wsymbol_0001_sunny.png',
       'Partly cloudy': 'https://cdn.worldweatheronline.com/images/wsymbols01_png_64/wsymbol_0002_sunny_intervals.png',
@@ -59,10 +62,14 @@ async function updateWeatherDataManually() {
       };
   });
 
+  // Connect to the database
     const client = await pool.connect();
     try {
+        // Start transaction
         await client.query('BEGIN');
         for (const data of manualWeatherData) {
+
+            // Insert or update weather data in the database for each city
             const insertQuery = `
                 INSERT INTO weather_data (id, city, latitude, longitude, temperature, humidity, air_pressure, wind_speed, weather_descriptions, observation_time, weather_icons, is_day)
                 VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12)
@@ -83,19 +90,24 @@ async function updateWeatherDataManually() {
             ];
             await client.query(insertQuery, values);
         }
+        // Commit transaction if successful
         await client.query('COMMIT');
     } catch (e) {
         console.error('Failed to update weather data:', e);
+        // Rollback transaction in case of an error
         await client.query('ROLLBACK');
     } finally {
+        // Release database client
         client.release();
     }
   }
 
-
+// Function to serve weather data via HTTP GET request
   async function getWeather(req, res) {
     try {
+        // Fetch weather data from the database and format the response
         const weatherData = await fetchAllWeatherData();
+        // Send formatted weather data as response
         const response = {
             data: weatherData.map(row => ({
                 type: 'weather',
@@ -122,4 +134,5 @@ async function updateWeatherDataManually() {
     }
 }
 
+// Export the functions for use in other modules
 module.exports = { updateWeatherDataManually, getWeather };

src/db/index.js

@@ -1,11 +1,15 @@
 const { Pool } = require('pg');
 const { DATABASE_URL } = require('../config');
 
+// Create a new pool instance with connection settings
 const pool = new Pool({
+  // Use the DATABASE_URL for connection string
   connectionString: DATABASE_URL,
+  // Disable SSL to allow connections from localhost
   ssl: {
     rejectUnauthorized: false
   }
 });
 
+// Export the pool for database operations elsewhere in the application
 module.exports = pool;

src/models/weatherModel.js

@@ -1,10 +1,12 @@
 const pool = require('../db');
 
+// Function to store multiple weather data entries into the database
 async function storeWeatherData(weatherData) {
     console.log('Storing weather data...');
     const client = await pool.connect();
     try {
         await client.query('BEGIN');
+        // Prepare and execute SQL to insert or update weather data for each entry
         for (const data of weatherData) {
             const insertQuery = `
                 INSERT INTO weather_data (id, city, latitude, longitude, temperature, humidity, air_pressure, wind_speed, weather_descriptions, observation_time, weather_icons, is_day)
@@ -35,9 +37,11 @@ async function storeWeatherData(weatherData) {
     }
   }
 
+  // Function to fetch all weather data from the database
   async function fetchAllWeatherData() {
     const client = await pool.connect();
     try {
+        // Execute a SELECT query to fetch all weather data
         const { rows } = await client.query('SELECT * FROM weather_data');
         return rows;
     } catch (error) {
@@ -48,4 +52,5 @@ async function storeWeatherData(weatherData) {
     }
 }
 
+// Export the functions for external use
 module.exports = { storeWeatherData, fetchAllWeatherData };

src/routes/subscriptionRoutes.js

@@ -1,7 +1,10 @@
 const express = require('express');
 const router = express.Router();
+// Import the addSubscription function from the subscription controller
 const { addSubscription } = require('../controllers/subscriptionController');
 
+// Define a POST route for subscriptions
 router.post('/subscribe', addSubscription);
 
+// Export the router for use in other parts of the application
 module.exports = router;

src/routes/weatherRoutes.js

@@ -2,8 +2,10 @@ const express = require('express');
 const { getWeather } = require('../controllers/weatherController');
 const router = express.Router();
 
+// Define a GET route for fetching weather data
 router.get('/api/weather', getWeather);
 
+// Swagger documentation for the /api/weather endpoint
 /**
  * @swagger
  * /api/weather:

src/services/emailService.js

@@ -2,13 +2,19 @@
 const nodemailer = require('nodemailer');
 const pool = require('../db');
 
+// Asynchronously send weather updates to all subscribers
 async function sendWeatherUpdates() {
     const client = await pool.connect();
     try {
+        // Retrieve a list of distinct cities from subscriptions
         const { rows: subscriptions } = await client.query('SELECT DISTINCT city FROM subscriptions;');
+        // Iterate over each city to fetch and send weather updates
         for (const { city } of subscriptions) {
+            // Fetch weather data for the current city
             const weatherData = await fetchWeatherDataForCity(city); 
+            // Retrieve all email addresses subscribed to the current city
             const { rows: subscribers } = await client.query('SELECT email FROM subscriptions WHERE city = $1;', [city]);
+            // Send an email with weather data to each subscriber
             for (const { email } of subscribers) {
                 await sendEmail(email, city, weatherData);
             }
@@ -20,14 +26,17 @@ async function sendWeatherUpdates() {
     }
 }
 
+// Asynchronously fetch weather data for a specific city
 async function fetchWeatherDataForCity(city) {
     const client = await pool.connect();
     try {
+        // SQL query to select temperature stats for the specified city
         const query = `
             SELECT MAX(temperature) AS max_temp, MIN(temperature) AS min_temp, AVG(temperature) AS avg_temp
             FROM weather_data
             WHERE city = $1;
         `;
+        // Execute the query and return the result
         const result = await client.query(query, [city]);
         return result.rows[0]; 
     } catch (error) {
@@ -38,8 +47,9 @@ async function fetchWeatherDataForCity(city) {
     }
 }
 
-
+// Asynchronously send an email to a recipient with weather data for a city
 async function sendEmail(recipient, city, weatherData) {
+     // Configure nodemailer with email service and authentication details
     let transporter = nodemailer.createTransport({
         service: 'gmail', 
         auth: {
@@ -48,6 +58,7 @@ async function sendEmail(recipient, city, weatherData) {
         }
     });
 
+    // Set up email options including recipient, subject, and body
     let mailOptions = {
         from: 'geo360.live@gmail.com',
         to: recipient,
@@ -66,6 +77,7 @@ async function sendEmail(recipient, city, weatherData) {
             Geo360 Team.`
     };
 
+    // Send the email and log the result or error
     transporter.sendMail(mailOptions, function(error, info){
         if (error) {
             console.log('Email send error:', error);

src/swaggerConfig.js

@@ -1,20 +1,24 @@
 const swaggerJsDoc = require('swagger-jsdoc');
 
+// Define Swagger options for API documentation
 const swaggerOptions = {
     definition: {
         openapi: '3.0.0',
+        // Provide basic information about the API (title, version, description)
         info: {
             title: 'Geo 360 Live Weather API',
             version: '1.0.0',
             description: 'A simple Express Weather API'
         },
+        // Define the server(s) the API is available on
         servers: [
             {
                 url: 'https://www.geo360live.tech'
             }
         ],
     },
+    // Specify the path(s) to files containing Swagger annotations for routes
     apis: ['./src/routes/*.js'], 
 };
 
-module.exports = swaggerJsDoc(swaggerOptions);
+module.exports = swaggerJsDoc(swaggerOptions);